Farm Industry News continued the countdown of the top 40 Most Fuel-efficient Tractors built in the past 10 years. Here are tractors 9 through 1, including a four-way tie at #5 and the "Fuel King."

Farm Industry News compiled the list of most fuel-efficient tractors with help from the Nebraska Tractor Test Lab. The test results from the last 10 years were used and include several new Tier 4 interim engines. The fuel efficiency ratings are based on the PTO test at rated engine speed. Find the related story here.

Special note: Rankings include all high-hp row-crop tractors (150+ hp) tested by the Nebraska Tractor Test Lab in the last 10 years. Nearly 200 models have been tested during this timeframe, but only the top 40 made the cut for being the best models on fuel. Three of all models tested are equipped with new Tier 4i emissions-compliant engines: Case IH Magnum 340, which ranked 3rd; John Deere 8335R, which ranked 4th, and; the John Deere 8360R IVT, ranking 22nd on the list. More Tier 4i tractors will be tested in 2012, and we will rank them all again at that time.

Also note that rankings are based on the PTO test at rated engine speed, which lab director Roger Hoy says is a good indicator because it is one that is calculated for all tractors and it is always run at the maximum level. (However, he advises tractor buyers to consider the other test measures, too, because power and fuel use will vary depending on the intended application. See tractortestlab.unl.edu <http://tractortestlab.unl.edu/> .)